Monthly Archives: March 2017

CNBP welcomes its latest PhD candidate Patrick Capon who is working on fluorophore-nanodiamond hybrid sensors at the University of Adelaide.

Patrick has previously gained a BSc Degree (advanced – double chemistry major) from Adelaide University which was subsequently followed by a Master of Philosophy (chemistry) also at Adelaide University – his thesis entitled, “Incorporation of N-Heterocyclic Carbenes and their Precursors into Metal-Organic Frameworks.”

Supervised by CNBP Chief Investigator Prof. Andrew Abell, Patrick will be working largely within the CNBP Recognise Theme but also undertaking collaborations with the Discover Theme focused on the use of fluorophore-nanodiamond hybrid sensors to detect relevant reactive oxygen species and reactive nitrogen species.

Other collaboration activity will include work with CNBP Biological Challenge Leader Prof. Stephen Nicholls and his team, as well as with Illuminate Theme Leader Associate Prof. Brant Gibson and researcher Dr. Phillip Reineck.

Currently a recipient of the Norman and Patricia Polglase Scholarship, Patrick has also just been awarded the prestigous MF & MH Joyner Scholarship in Science from the University of Adelaide.

CNBP is happy to announce its newest PhD student Kathryn Palasis who is located at the University of Adelaide.

Kathryn who was was recently selected as the 2017 recipient of the Cedric Stanton Hicks Research Scholarship, will be working on switchable molecules and their applications in medicinal chemistry – with a particular emphasis on the design of photoswitchable protease inhibitors and the development of hypoxia-sensitive sensors and probes.

Graduating from Adelaide University with a Bachelor of Advanced Science (Double Chemistry Major) Kathryn previously won the G. M. Badger Prize for best weighted overall performance in courses of Level III Chemistry. This was followed by an Honours degree, also from Adelaide University where her thesis was titled “Synthesis and Activity of Switchable Azobenzene-Based Proteasome Inhibitors.”

As a PhD student, Kathryn will be working with her supervisor Prof Andrew Abell (CNBP Chief Investigator) on synthesising photoswitches of biological activity. She will also be collaborating with CNBP Investigator Robert McLaughlin (and his work on optical probes) and also Jeremy Thompson, CNBP Chief Investigator (and his work in the ‘Spark of Life’ theme).

CNBP scientists Dr Ivan Maksymov and Prof Andy Greentree at RMIT University have shown bubbles can detect sound with light in their latest publication in the area of photo-acoustics.

“Bubbles can be a boon for detecting the kind of ultrasound used in medicine as air is less dense than water” explains Dr Ivan Maksymov, “so ultrasound can squeeze a bubble more than the water surrounding it”.

To detect the change in size, Ivan showed that the bubbles could change the amount of light that passed through a gold membrane with nanosized holes in it. “It’s incredible work, I’m really excited by how Ivan has brought together these different kinds of Physics to create something quite new”, said the study’s co-author Prof Andy Greentree.

To detect the effects of sound on the bubble, on light, Ivan had to develop new computational models. The team say that their work may be useful in the development of an optical hydrophone for detecting ultrasound inside the body. “It will give us a new and potentially more sensitive way to ‘see’ with sound” says Ivan.

The work was published in the journal Physical Review A on 13th March 2017 and was funded by the Australian Research Council Centre of Excellence for Nanoscale BioPhotonics.

Abstract: The development of a fast and reliable whispering gallery mode (WGM) simulator capable of generating spectra that are comparable with experiment is an important step forward for designing microresonators. We present a new model for generating WGM spectra for multilayer microspheres, which allows for an arbitrary number of concentric dielectric layers, and any number of embedded dipole sources or uniform distributions of dipole sources to be modeled. The mode excitation methods model embedded nanoparticles, or fluorescent dye coatings, from which normalized power spectra with accurate representation of the mode coupling efficiencies can be derived. In each case, the emitted power is expressed conveniently as a function of wavelength, with minimal computational load. The model makes use of the transfer-matrix approach, incorporating improvements to its stability, resulting in a reliable, general set of formulae for calculating whispering gallery mode spectra. In the specific cases of the dielectric microsphere and the single-layer coated microsphere, our model simplifies to confirmed formulae in the literature.

The work was published online in the journal Rapid Communications in Mass Spectrometry on 9th March 2017 and was funded by the Australian Research Council Centre of Excellence for Nanoscale BioPhotonics.

CNBP Associate Investigator A/Prof Kevin Pfleger, from the Harry Perkins Institute of Medical Research, has won the Intrapreneur category, as well as receiving the coveted City of Perth Strategic Alliance Award at the Business News 40under40 Awards in Perth on Wednesday 8th March.

“I’m passionate about helping my fellow scientists by facilitating a network of mentors that accelerate the transition of discoveries in the laboratory to treatments for the community,” A/Prof Pfleger said.

More information can be found on the Harry Perkins Institute of Medical Research news site.

The Macquarie University node of CNBP welcomes a new PhD student to the team – Yuan Liu.

Yuan will study under the supervision of Center Deputy Director Prof. Ewa Goldys and Centre Research Fellow A/Prof. Guozhen Liu.

Her project will explore the construction of a novel biosensing platform for quantitatively detecting exosomes which can be employed as a potential biomarker for non-invasive disease diagnosis.

Previously, Yuan obtained her Masters Degree of Medicine from Shihezi University, China. During that time she majored in pharmaceutical analysis and her research was focused on the construction, characterization and application of electrochemical and gas sensors under the guidance of Prof. Hui Tang and Prof. Yingchun Li.

A new publication from CNBP researchers (lead author Aziz Ul Rehman pictured) reports on the application of hyperspectral imaging in combination with fluorescence spectroscopy and chemical quenching to provide a new methodology to investigate cell metabolism.

The work has just been reported in the journal ‘Biomedical Optics Express’ and is accessible online.

Journal: Biomedical Optics Express.

Title: Fluorescence quenching of free and bound NADH in HeLa cells determined by hyperspectral imaging and unmixing of cell autofluorescence.

Abstract: Carbonyl cyanide-p-trifluoro methoxyphenylhydrazone (FCCP) is a well-known mitochondrial uncoupling agent. We examined FCCP-induced fluorescence quenching of reduced nicotinamide adenine dinucleotide / nicotinamide adenine dinucleotide phosphate (NAD(P)H) in solution and in cultured HeLa cells in a wide range of FCCP concentrations from 50 to 1000µM. A non-invasive label-free method of hyperspectral imaging of cell autofluorescence combined with unsupervised unmixing was used to separately isolate the emissions of free and bound NAD(P)H from cell autofluorescence. Hyperspectral image analysis of FCCP-treated HeLa cells confirms that this agent selectively quenches fluorescence of free and bound NAD(P)H in a broad range of concentrations. This is confirmed by the measurements of average NAD/NADH and NADP/NADPH content in cells. FCCP quenching of free NAD(P)H in cells and in solution is found to be similar, but quenching of bound NAD(P)H in cells is attenuated compared to solution quenching possibly due to a contribution from the metabolic and/or antioxidant response in cells. Chemical quenching of NAD(P)H fluorescence by FCCP validates the results of unsupervised unmixing of cell autofluorescence.